"4-Way suspension" work alike?

[PhillipM]

Well, sorry, I can't argue with someone who doesn't know what damping is, can't define it without looking up a flaky Wiki entry (in fact, if you go on Wiki you'll find there is there correct definition for mechanical damping is there, you just completely missed it in your search as you didn't know what you were looking for*), and doesn't want to change his definition because in his head it's 'fact'

If we're going for facts, the facts are these:

1. You are adding a spring. Which direction it works in is irrelevant, spring rate is spring rate.
2. You are not adding any additional, intentional damping force.

So, where, out of those two FACTS as you like to quote, does the idea enter your mind that you're changing the damping?
Done any of that basic math yet? Math is always good for facts, it stops people's brains getting in the way.


*wiki....

In physical systems, damping is produced by processes that dissipate the energy stored in the oscillation. Examples include Viscous drag in mechanical systems

[Piledriver]

It would be interesting to plot the combined curve.
I would like to see the compression only progressive spring that pulls against the torsion springs.

I could see it with a pair of opposing compression springs (could be different rates for compression and extension)with a floater actually attached to the suspension, in fact that was not unusual at some levels of racing back in the day.

[PhillipM]

It doesn't need to.

[Piledriver]

It doesn't need to.

I'll buy we end up with a equivalent model to a highly progressive spring assy that we cannot mount.
(probably doable with some sort of eccentric bellcrank setup but not a simple bolt on a torsion bar suspension)

If that is the case (or not) it works extremely well.
I would like to understand how best to set it up, as this setup is easily installable, adjustable and springs can be swapped like coil overs and adjusted to operate at different ride heights, unlike a fixed progressive spring that does not exist and we cannot buy.

[PhillipM]

Your spring is not only soft in the middle of the range, it has a step change, just like using a divider stop on a twin-sprung coilover. It's soft, then steps up to a secondary rate, that's all.
You don't even need to buy anything, you can do it with the standard torsion leaves if you have adjusters on the beam.

[Piledriver]

Your spring is not only soft in the middle of the range, it has a step change, just like using a divider stop on a twin-sprung coilover. It's soft, then steps up to a secondary rate, that's all.
You don't even need to buy anything, you can do it with the standard torsion leaves if you have adjusters on the beam.

That might be true if I had 4 torsion bars up front and out back.
(Type3=single full width bar goes across the car from each side, top bar is a sway bar)

Unless I implement the split/locked center swaybar version front and rear that isn't happening.

I edited my above post as you posted, so what you responded to may have changed somewhat.

[PhillipM]

Then just buy a standard coilover, and set the spring to come after the leaves, or take some leaves out of the pack and do the same if you want it even softer, just as cheap, much easier to get hold of. Or ditch the leaves completely and just use the coilover with twin springs if your mounts are up to it, gets rid of some of the inherent friction issues of the leaf pack.

[Piledriver]

Thank you for providing an equivalent model and explanation of how it works.

Are suspension dynos a thing?
(apparently, just not common around here)
I'd like to know what the setup i have works out to as to the primary/secondary springs and damping.
(or could it be calculated as at least the rear setup is bog std T1 IRS geometry?)

...So all I have to do to get the equivalent to what I have is spend ~$3K-5K to switch to dual spring coil overs, carefully set up so the secondary spring kicks in just at ride height, and lose the easy independent ride height vs transition point adjustment, and the ability to preload/unload.

I think I'll keep the setup i have that works, now...
it seems it can work reasonably well after all for a simple $100 one hour bolt on.

BTW, T3s have torsion bars (not leaves) front and rear, needle bearings up front top and bottom.
(front beam rubber mounted, two full width crossing torsion bars lower, sway bar across upper, rear irs same as t1, just on a rubber mounted subframe)

[KentT]

Well, sorry, I can't argue with someone who doesn't know what damping is,

Seems arguing is something you are very practiced at -- and enjoy doing...

I know what damping is -- it is you who seems to insist that damping can only be done via hydraulics... that if it is done mechanically it is simply an "added spring"...

Damping describes its intended purpose, not the mechanics of how that purpose is achieved.

For example, harmonic dampers are often fixed to crankshafts -- and they certainly have no hydraulics involved....

[PhillipM]

I'm not insisting it is only done by hydraulics at all - nowhere in this thread will you see me state anything like that, that's just yet another thing your head has assumed to be true. In fact if you read the thread you'll see I also work on friction disc dampers (and visco-elastic or fluid mounts too), which you'll probably have to look up on wiki again.

You will find a harmonic damper is either a fixed mass to change the resonant frequency (not strictly a damper but a simple frequency change due to mass), or they have two parts with visco-elastic fixing between the two (Note, there are also some high-performance versions which do use hydraulic damping using silicone oil, just like your hydraulic suspension damper), which allows the two halves to run out of phase to reduce peak shocks/vibration, they usually have either internally damped rubber or a friction disc between the two performing the role of dissipating some of the energy difference between the two halves without resulting in a secondary harmonic in the outer ring.
Basically, the coupling is the same as the spring in your suspension and the damping is carried out by the rubber/friction disc in the unit to prevent the outer becoming excited - the same as if you lost control of the hub mode vibration through cavitation or a knackered damper*


*Ever seen a car with a knackered damper bounce the wheel in the air even over what looks like a smooth surface? Same thing. Fortunately your car has hydraulic damper which generates forces far in excess of what's required because it has to control the sprung mass as well as the unsprung one, so it's pretty damned irrelevant anyway. Nobody adds mass to the hubs to get you out of excitation modes caused by the springs...

[PhillipM]

BTW, T3s have torsion bars (not leaves) front and rear, needle bearings up front top and bottom.
(front beam rubber mounted, two full width crossing torsion bars lower, sway bar across upper, rear irs same as t1, just on a rubber mounted subframe)

My apologies, I didn't realise that's what you were running, but for anyone with 4 torsion leaves, or twin torsion leaves/bars upper and lower, you can achieve this without spending a penny simply by staggering the leaves.
You can also do the same thing with your setup simply with a single light coilover spring - which would be easier to find than your 4-way setup - and set your torsion bars to come in after the spring/just past ride hight.
Yes, damper dynos are a thing, I've a relatively basic one here, but also have access to full hydraulic 7 post rigs, which are eye watering money.

[KentT]

... which you'll probably have to look up on wiki again.

1. I know what harmonic dampers are and how they operate. I first replaced one almost 50 years ago...

2. I know what viscous couplings are and how they operate. I've owned and maintained viscous 4WD/AWD systems.

3. I went to wikipedia and cited it not to find out a definition of damping, but to show YOU that I was using a commonly-used definition of the term.

4. One softer spring can dampen another stronger spring -- it is often done on the mechanical linkage for governors on small engines, for example, to provide smooth throttle control without surging/oscillation... It is NOT just "changing the base spring rate" that you seem to insist is the case.

5. If you can do something more than insult others, perhaps we could have a meaningful discussion. But, because you seem to think everyone but you is an idiot, that doesn't appear likely.

[sideshow]

I stumbled across this following a 4x4 thread about adding tennis balls to coil springs, but this company's PDF offers steering dampeners based on four way shocks (page 3) ? The other odd claim (page 2) is a return to center steering aid.
http://www.oppositelock.co.za/wp-conten ... ension.pdf

[KentT]

I stumbled across this following a 4x4 thread about adding tennis balls to coil springs, but this company's PDF offers steering dampeners based on four way shocks (page 3) ? The other odd claim (page 2) is a return to center steering aid.
http://www.oppositelock.co.za/wp-conten ... ension.pdf

Thanks for that current link. It seems that this may be the progeny of the original 4-Way design from "Down Under", now focused entirely on off-road.

(If you've ever driven a "rock-crawler" you can see the need for these, especially without power steering. I also have a SxS/UTV with rack and pinion steering, and "fighting the steering wheel" to keep it centered can get very tiring, very quickly, when crawling rocks in streambeds, etc. -- not to mention the tendency for rocks to tear the steering wheel from your grip.)

I'll try contacting them, and see if I can find out what the diameter of those steering stabilizers are, and the spring rate of the springs used...

[KentT]

Emailed Tough Dog -- will see if they respond.

Going with the idea of "Return-to-Center" steering stabilizers, I found additional companies building those. Roadmaster markets them for RVs and motorhomes. I'm also finding a "Profender" brand out of Malaysia. Here's a pic of their lower spring mount:



Problem with steering stabilizers may be that length/spring rate may be an issue -- in addition to price. Those Roadmaster ones are VERY pricey...